Knowledge of risk factors and early detection methods toward breast cancer among healthcare workers in Kinshasa, Democratic Republic of the Congo

Abstract Background Breast cancer (BC) is the most prevalent cancer among women, and it typically presents late in developing countries like the Democratic Republic of the Congo (DRC), leading to higher mortality rates. Late detection at advanced stages of breast cancer can be attributed to the absence of appropriate screening programs and low levels of awareness. Aims To evaluate the level of BC knowledge among healthcare workers (HCWs) and identify determinants of good BC knowledge. Methods and results An analytical cross‐sectional survey was conducted from March 1 to 31, 2022 involving HCWs practicing in Kinshasa, DRC. Data were collected using a questionnaire administered through direct interviews. Bivariate and multivariate regression techniques were applied. The study interviewed 543 HCWs, with a median age of 35 years (interquartile range: 29–43). Of these, 61% had good BC knowledge, while 39% had poor BC knowledge. Multivariate analysis revealed that HCWs aged 50 years and over (adjusted odds ratio [aOR] = 2.3 [1.2–4.5]), female HCWs (aOR = 1.8 [1.1–2.4]), HCWs working in public healthcare facilities (aOR = 1.5 [1.1–2.5]), and HCWs who had received training on BC (aOR = 1.9; 95% CI: 1.5–3.3) were determinants of good BC knowledge. Conclusion This study found that 61% of the surveyed HCWs had good BC knowledge. However, there is still room for improvement in terms of knowledge dissemination. Therefore, it is important to implement continuing medical education programs that focus on raising awareness and improving BC knowledge among HCWs.


| INTRODUCTION
Breast cancer (BC) is the most prevalent cancer in women worldwide, 1 including the Democratic Republic of the Congo (DRC). 2 Despite significant advances in the treatment of BC, the outcome is still desperate in low-income countries, including the DRC. 3,4Late diagnosis is a primary reason for the poor prognosis.Early detection of BC is associated with better prognosis, reduced morbidity, and mortality. 5Late-stage presentation and limited access to screening and treatment services contribute to elevated mortality rates associated with BC.Early detection, through increased awareness of risk factors and available screening methods, is paramount in mitigating the burden of this disease.The goal of the World Health Organization's (WHO) new global initiative to combat BC is to reduce mortality from BC worldwide by 2.5% per year, thereby averting 2.5 million deaths from BC worldwide between 2020 and 2040.Three key components are needed to achieve this goal: BC comprehensive management, prompt diagnosis, and promoting health for early detection. 6asures should therefore be taken to achieve this objective.Educating healthcare workers (HCWs), and the community at large about the early warning signs and symptoms of BC and learning about screening methods are crucial components of early diagnosis. 7However, it should also be emphasized that effective cancer prevention requires HCWs to take greater account of the various risk factors, through frequent public awareness campaigns. 8Previous researches have demonstrated that both HCWs and patients have inadequate knowledge regarding BC associated factors. 7,9,10Other studies have reported misconceptions among HCWs (such as the belief that prayer can make BC disappear, 11 or the belief that keeping money in the bra causes BC 12 ).HCWs, being at the forefront of healthcare delivery, play a pivotal role in disseminating crucial information about BC to the community.Their knowledge and awareness not only influence their practices but also contribute significantly to public health initiatives.
Good knowledge and awareness are essential for early diagnosis and effective prevention.HCWs have the power to favorably affect patients' attitudes and beliefs regarding screening procedures and to significantly affect their overall perspective on them. 13HCWs are often the primary point of contact, not only for their patients but also for parents and relatives, to provide correct advice and information about BC and its screening.Thus, educating HCWs about BC and its

| Study site and population
This analytical cross-sectional study was conducted in Kinshasa, the capital of the DRC located in the south-western part of the country (longitude 15 18 0 48 00 East and latitude 4 19 0 39 00 South).The city covers an area of 9965 km2 and has an estimated population of 17 million in 2021.Kinshasa is divided into 35 health zones (ZS) and serves as a hub for health services for the entire country and neighboring provinces.
All doctors and nurses from the city's various healthcare facilities were judged eligible for this study, and they were chosen at random.
An HCW was excluded from the study if they worked in a healthcare facility that had not consented to participate, or if they were on vacation or absent from work on the day of data collection.Private clinics, general referral hospitals, and health centers were all included in the study.Between March 1 and 31, 2022, data were collected.
A minimum sample size of 317 was determined by random sampling using the formula: n = z 2 pq/d 2 , with a 95% confidence interval (95% CI) standard deviation (1.96), a prevalence of good BC knowledge in Congolese women in Kinshasa of 22.09%, 14 a precision error of 5%, and a non-response rate of 20%.The study randomly selected 10 health zones (HZs) from a list of 35 HZs in Kinshasa in the first stage.In the second stage, different HCWs were randomly selected and interviewed for the study.
Out of the 600 questionnaires distributed, 557 were returned, and 543 of the returned questionnaires were found to be complete and included in analysis.Thus, the response rate was 90.5%.

| Data collection and study variables
The study was conducted from March 1 to 31, 2022, and utilized a semi-structured questionnaire that was developed from a literature review. 7The questionnaire was pre-tested with 20 HCWs to ensure clarity of meaning and appropriate use of language, taking into account expert opinion.The face-to-face interviews were conducted by final-year medical students who received orientation on the study protocol and questionnaire administration skills.The interviews were supervised by the principal investigator (SMMS).
Ten interviewers were recruited and provided with mock survey tests, a detailed interpretation of the survey questionnaire, and training in the context of the current survey.Before asking participants to complete the questionnaire, the researchers gave them an explanation of the study's goal and methodology and got their signed informed consent.Participants' responses to the survey took an average of 15-20 min.Written informed consent was obtained from all eligible participants for the interview after they were informed about the study's purpose.
After conducting a comprehensive literature review, we developed survey questions and organized the questionnaire into four parts.
The first part comprised socio-demographic and professional characteristics: age (20-29, 30-39, 40-49, or ≥50 years), gender (female or male), type of healthcare facility (private clinic or public hospital), medical qualification (physician or nurse), number of years of professional practice (<5, 5-9, or ≥10 years), having received training on BC in the 24 months preceding the survey (yes or no), and having ever had a family member or relative who had suffered from BC (yes or no).
The second section comprised the questions on BC knowledge, categorized into four sections: signs and symptoms, potential risk factors, and screening methods.
For the second part, HCWs were asked to respond with either "yes," "no," or "I do not know."Responses were scored dichotomously, with zero point given for incorrect or "I do not know" responses and one point given for each correct answer.The total score was calculated by adding up the points obtained, with a maximum score of 29.Scores were then categorized as good knowledge (18-29 points, 60% or more of correct answers) or either poor knowledge (0-17 points, less than 60% of correct answers).

| Statistical analysis
Microsoft excel was used to enter and encode the data.STATA version 16.0 was used for the statistical analyses.
To perform a descriptive analysis, we computed medians with interquartile ranges (IQR) for non-normally distributed quantitative variables, as confirmed by the Shapiro test, and proportions for qualitative variables (frequencies, percentages, and Wilson's 95% CI).To compare the medians across various variable categories, we employed the Mann-Whitney U test or, when advised, the ANOVA test.
In this study, we considered good knowledge as our dependent variable.To find the variables linked to good BC knowledge, we first performed a bivariate analysis using the Chi-squared test and stepwise method for multiple logistic regression.The regression model contained explanatory variables with a bivariate test value of 0.25.pvalues less than .05were considered as statistically significant.

| Ethical considerations
Before the interviews, participants gave their informed consent, and there was no payment or other incentive given to them as part of the study.Participants received guarantees that the information they provided would be kept private and that they could leave the study at any time, for any reason.

| Socio-demographic characteristics of participants
A total of 543 HCWs completed the survey, of whom 192 (35.4%) were physicians and 351 (64.6%) were nurses.The median age (IQR) of the participants was 35 years (29-43).Over a third (35.4%) of respondents were aged between 30 and 39, and 67.6% were male.A third (32.2%) of respondents worked in private healthcare facilities and 67.8% in public healthcare facilities.Respondents had been in clinical practice experience for a median of 5 years (3-10) and only 32.4% had reported receiving a training session on BC in the 24 months preceding the survey.Two hundred and eighteen (40.2%) participants reported having a family member or close friend who had ever suffered from BC (Table 1).

| Participants' knowledge of breast cancer
The median knowledge score was 19 (15-23) out of a total of 29 points.Table 1 shows that respondents aged 50 or over, female respondents, physicians, and those who had received training on BC had significantly higher median scores than others ( p < .05).We classified a score of 0-17 as a poor of BC knowledge and a score ≥18 as a good BC knowledge.Of the participants, 331 (61.0%) had a good level and 212 (39.0%) had a poor level of BC knowledge (Table 1).
More than 70% of the respondents identified a family history of BC, oral contraceptive use, and radiation exposure as potential risk factors for developing BC.However, only around 50% recognized smoking, alcohol consumption, a diet rich in animal fats, late first pregnancy, and obesity as potential risk factors for BC.
In the section on signs and symptoms of BC, the majority of participants recognized that a change in breast shape (asymmetry) and breast size could be signs of BC, with 85.5% and 74.4% of participants respectively indicating this.Over 81% and 77.4% of respondents respectively recognized abnormal breast discharge and a painful or painless breast lump as signs of BC.Breast ulceration and pain were recognized as signs of BC by 83% of respondents.
Regarding the methods used to diagnose BC, more than 70% of participants gave the correct answer for anatomopathological examination of breast tissue (70.5%) and BSE (75.9%).Mammography was recognized as a method of detecting BC by 80.5% of respondents, while only 63.9% recognized CBE and 36.8%recognized ultrasound (Table 2).

| Breast self-examination's knowledge
Table 3 shows the results regarding knowledge and practice of BSE.In general, 484 (89.1%) participants recognized BSE as an effective tool for the early detection of BC.Among them, 267 (49.2%) had received BSE training.A total of 200 (36.8%)participants chose to start BSE at puberty, while 122 (22.5%) preferred to start at the age of 20.The majority (50.1%) agreed that 1 week after menstruation is the best time to practice BSE, and 282 participants (51.9%) thought BSE should be done daily.Less than half (49.2%) knew that BSE should be done by the person herself, and 438 (80.7%) said that in the event of an abnormality, a physician should be consulted.Finally, the vast majority (88.2%) agreed that BSE is a good practice.

| Clinical breast examination's knowledge
The findings concerning knowledge and practice of CBE are illustrated in Table 4. 88.4% (480) of participants recognized the effectiveness of CBE in detecting BC.Among the respondents, 38.0% (208) preferred to have an HCW conduct the CBE, 26.1% (142) believed that mammography should be included in CBE, 25.1% (136) recommended performing CBE monthly, and 14.5% (79) yearly intervals.

| Mammography's knowledge
A majority of the participants, 469 (86.4%), acknowledged mammography as an effective tool for the early detection of BC.Out of these, 354 (65.2%) correctly identified mammography as a radiological examination.231 (42.5%) agreed that mammography should be initiated at the age of 40, while 210 (38.7%) mentioned that mammography should be performed when a lump is detected during BSE or CBE (as presented in Table 5).

| Determinants of participants' good knowledge of breast cancer
Table 6 presents the results of the bivariate analyses conducted to determine the association between the participants' sociodemographic and professional characteristics and their level of BC knowledge.The study found significant associations between good BC knowledge and variables such as age, gender, medical title, and receiving training on BC within the 24 months before the survey.
The logistic regression revealed that respondents aged ≥50 years had higher chances of having good BC knowledge compared to others (adjusted odds ratio [aOR] = 2.3; 95% CI: 1.2-4.5;p = .009).Furthermore, female participants were significantly more likely to have good knowledge than their male counterparts (aOR = 1.8; 95% CI: 1.1-2.4;p = .017).Respondents working in public healthcare facilities had higher chances of having good BC knowledge compared to those working in private clinics (aOR = 1.5; 95% CI: 1.1-2.5;p = .045).The results also showed that respondents who received training on BC had significantly higher odds of having good BC knowledge than those who did not receive training (aOR = 1.9; 95% CI: 1.5-3.3;p < .001)(Figure 1).

| DISCUSSION
For BC to be detected early and treated as effectively as possible, awareness and knowledge are essential.The level of BC knowledge among HCWs is a significant factor in the optimal management of their patients.It is obvious that when HCWs actively participate in health education and act as positive role models for the community, health will improve. 15This study, the first of its kind, aimed to T A B L E 2 Percentage of correct answers to questions relating to participants' knowledge of breast cancer.evaluate the knowledge of BC and its screening among HCWs practicing in Kinshasa.
The study found that 61% (95% CI: 56.8%-65.0%) of the participants had good BC knowledge, particularly concerning its risk factors, signs and symptoms, and diagnostic methods.Compared to other studies, 7,12,[15][16][17] the rate of good BC knowledge among our cohort appears to be higher.
However, despite this, this research emphasizes the necessity of further education and training on BC for HCWs, given that only 32.4% of respondents had received training on BC in the previous 24 months.Such training should aim to improve the knowledge of HCWs in our setting, which will ultimately lead to better health outcomes for patients.
The study revealed that HCWs in our cohort were most familiar with a family history of BC, radiation exposure, and oral contraceptive use as risk factors for BC, while early menarche, late menopause, and physical inactivity were the least well-known.These results are in line with previous researches done on HCWs in various countries. 7,15,18sed on our findings, we recommend that training HCWs should emphasize the risk factors for BC, particularly those that are less well known.Despite being the key to BC awareness and screening, most studies have shown that HCWs have poor knowledge and practice of these early detection methods.among HCWs, as we found that having received BC training was a predictor of a good level of knowledge about BC.According to the WHO, public health education measures aimed at making women and their families aware of the BC signs/symptoms, and the importance of early detection and appropriate treatment, contribute to more women consulting an HCW as soon as BC is suspected and before any cancer reaches an advanced stage. 6These advances are possible even in the absence of mammography, a technique that is currently difficult to implement in a large number of countries.Public education must go hand in hand with education for HCWs about the signs/symptoms of early-stage BC, so that women can be referred for diagnosis if necessary. 6e study examines BC knowledge among HCWs in Kinshasa, highlighting its limitations, strengths, and hypotheses.Among the limitations, the cross-sectional design hinders causality and general- screening is an important target for future interventions aimed at improving BC outcomes in the DRC.Understanding the baseline knowledge of HCWs in Kinshasa regarding BC risk factors and early detection methods is essential for designing targeted interventions.Furthermore, to the best of our knowledge, no research has been done in Kinshasa, or anywhere else in the DRC, specifically on the assessment of BC knowledge among HCWs.This study aims to assess the knowledge of HCWs regarding BC and to identify factors associated with a good level of BC knowledge that could be targeted for future educational interventions.Understanding the current understanding and awareness within this vital demographic can help identify potential gaps and challenges that may hinder effective BC prevention and early diagnosis strategies.The findings of this study have the potential to inform tailored educational programs for HCWs, thereby enhancing their ability to convey accurate and impactful information to the broader community.
The third part aimed to evaluate the knowledge of respondents on breast self-examination (BSE).Participants were asked if they were aware of BSE and whether they believed it was beneficial for the early detection of BC.Other questions related to BSE included at what age should BSE be started, how often should the BSE be carried out, what is the best time to do BSE, who should carry out BSE, and in the event of a breast abnormality during BSE, what action would you recommend.The final part evaluated the knowledge of clinical breast examination (CBE) and mammography.The Cronbach's alpha coefficient calculated for the breast cancer (BC) knowledge and screening items yielded an internal consistency reliability of 0.895.
izability, while random sampling and self-reporting of data pose potential issues of selection and memory bias.However, the large sample size enhances reliability, and the study establishes a strong foundation for future research.Strengths include a comprehensive assessment of breast cancer knowledge among healthcare professionals, providing valuable data for targeted interventions.The implicit hypothesis is that improving breast cancer knowledge among healthcare professionals can lead to more effective screening and management practices.

T A B L E 6
Bivariate analysis of the breast cancer knowledge level.Variable BC knowledge level Unadjusted odds ratio [95% confidence interval]p-value Good (n = 331) n (%)Poor (n = 212) n (%)

F
I G U R E 1 Logistic regression of good breast cancer knowledge's determinants.5 | CONCLUSION This study revealed that 61% of HCWs had good knowledge of BC, with age ≥50 years, female gender, public healthcare facility, and receiving training on BC in the last 24 months before the survey being significant determinants of good BC knowledge.Based on these findings, we suggest continuous and efficient BC training for HCWs.Further studies on HCWs from other regions of the DRC can provide insights to enhance the comprehension of BC awareness among Congolese HCWs.The future prospects of this study include exploring the long-term impacts of training programs, identifying determinants of awareness among HCWs, and collaborating with other stakeholders to enhance public health.
Knowledge and practice of clinical breast examination (CBE).